new file mode 100644
--- /dev/null
+++ b/src/http/v3/ngx_http_v3_parse.h
@@ -0,0 +1,145 @@
+
+/*
+ * Copyright (C) Roman Arutyunyan
+ * Copyright (C) Nginx, Inc.
+ */
+
+
+#ifndef _NGX_HTTP_V3_PARSE_H_INCLUDED_
+#define _NGX_HTTP_V3_PARSE_H_INCLUDED_
+
+
+#include <ngx_config.h>
+#include <ngx_core.h>
+#include <ngx_http.h>
+
+
+typedef struct {
+    ngx_uint_t                      state;
+    uint64_t                        value;
+} ngx_http_v3_parse_varlen_int_t;
+
+
+typedef struct {
+    ngx_uint_t                      state;
+    ngx_uint_t                      mask;
+    uint64_t                        value;
+} ngx_http_v3_parse_prefix_int_t;
+
+
+typedef struct {
+    ngx_uint_t                      state;
+    uint64_t                        id;
+    ngx_http_v3_parse_varlen_int_t  vlint;
+} ngx_http_v3_parse_settings_t;
+
+
+typedef struct {
+    ngx_uint_t                      state;
+    ngx_uint_t                      insert_count;
+    ngx_uint_t                      delta_base;
+    ngx_uint_t                      sign;
+    ngx_uint_t                      base;
+    ngx_http_v3_parse_prefix_int_t  pint;
+} ngx_http_v3_parse_header_block_prefix_t;
+
+
+typedef struct {
+    ngx_uint_t                      state;
+    ngx_uint_t                      length;
+    ngx_uint_t                      huffman;
+    ngx_str_t                       value;
+    u_char                         *last;
+    u_char                          huffstate;
+} ngx_http_v3_parse_literal_t;
+
+
+typedef struct {
+    ngx_uint_t                      state;
+    ngx_uint_t                      index;
+    ngx_uint_t                      base;
+    ngx_uint_t                      dynamic;
+
+    ngx_str_t                       name;
+    ngx_str_t                       value;
+
+    ngx_http_v3_parse_prefix_int_t  pint;
+    ngx_http_v3_parse_literal_t     literal;
+} ngx_http_v3_parse_header_t;
+
+
+typedef struct {
+    ngx_uint_t                      state;
+    ngx_http_v3_parse_header_t      header;
+} ngx_http_v3_parse_header_rep_t;
+
+
+typedef struct {
+    ngx_uint_t                      state;
+    ngx_uint_t                      length;
+    ngx_http_v3_parse_varlen_int_t  vlint;
+    ngx_http_v3_parse_header_block_prefix_t  prefix;
+    ngx_http_v3_parse_header_rep_t  header_rep;
+} ngx_http_v3_parse_headers_t;
+
+
+typedef struct {
+    ngx_uint_t                      state;
+    ngx_http_v3_parse_header_t      header;
+    ngx_http_v3_parse_prefix_int_t  pint;
+} ngx_http_v3_parse_encoder_t;
+
+
+typedef struct {
+    ngx_uint_t                      state;
+    ngx_http_v3_parse_prefix_int_t  pint;
+} ngx_http_v3_parse_decoder_t;
+
+
+typedef struct {
+    ngx_uint_t                      state;
+    ngx_uint_t                      type;
+    ngx_uint_t                      length;
+    ngx_http_v3_parse_varlen_int_t  vlint;
+    ngx_http_v3_parse_settings_t    settings;
+} ngx_http_v3_parse_control_t;
+
+
+ngx_int_t ngx_http_v3_parse_varlen_int(ngx_connection_t *c,
+    ngx_http_v3_parse_varlen_int_t *st, u_char ch);
+ngx_int_t ngx_http_v3_parse_prefix_int(ngx_connection_t *c,
+    ngx_http_v3_parse_prefix_int_t *st, ngx_uint_t prefix, u_char ch);
+
+ngx_int_t ngx_http_v3_parse_headers(ngx_connection_t *c,
+    ngx_http_v3_parse_headers_t *st, u_char ch);
+ngx_int_t ngx_http_v3_parse_header_block_prefix(ngx_connection_t *c,
+    ngx_http_v3_parse_header_block_prefix_t *st, u_char ch);
+ngx_int_t ngx_http_v3_parse_header_rep(ngx_connection_t *c,
+    ngx_http_v3_parse_header_rep_t *st, ngx_uint_t base, u_char ch);
+ngx_int_t ngx_http_v3_parse_literal(ngx_connection_t *c,
+    ngx_http_v3_parse_literal_t *st, u_char ch);
+ngx_int_t ngx_http_v3_parse_header_ri(ngx_connection_t *c,
+    ngx_http_v3_parse_header_t *st, u_char ch);
+ngx_int_t ngx_http_v3_parse_header_lri(ngx_connection_t *c,
+    ngx_http_v3_parse_header_t *st, u_char ch);
+ngx_int_t ngx_http_v3_parse_header_l(ngx_connection_t *c,
+    ngx_http_v3_parse_header_t *st, u_char ch);
+ngx_int_t ngx_http_v3_parse_header_pbi(ngx_connection_t *c,
+    ngx_http_v3_parse_header_t *st, u_char ch);
+ngx_int_t ngx_http_v3_parse_header_lpbi(ngx_connection_t *c,
+    ngx_http_v3_parse_header_t *st, u_char ch);
+
+ngx_int_t ngx_http_v3_parse_control(ngx_connection_t *c, void *data, u_char ch);
+ngx_int_t ngx_http_v3_parse_settings(ngx_connection_t *c,
+    ngx_http_v3_parse_settings_t *st, u_char ch);
+
+ngx_int_t ngx_http_v3_parse_encoder(ngx_connection_t *c, void *data, u_char ch);
+ngx_int_t ngx_http_v3_parse_header_inr(ngx_connection_t *c,
+    ngx_http_v3_parse_header_t *st, u_char ch);
+ngx_int_t ngx_http_v3_parse_header_iwnr(ngx_connection_t *c,
+    ngx_http_v3_parse_header_t *st, u_char ch);
+
+ngx_int_t ngx_http_v3_parse_decoder(ngx_connection_t *c, void *data, u_char ch);
+
+
+#endif /* _NGX_HTTP_V3_PARSE_H_INCLUDED_ */